BMR Installation Help - Stiffness Issue

[Jsolman]

Recently had the following parts added to the rear suspension setup on my S550 GT 2018:
Ford Performance Knuckle to Toe Link Bearing Assembly M-5A46—M
BMR IRS Rear Lower Control Arm Bearing Kit BK055
BMR Rear Upper Control Arm Camber Links UCA762
BMR Adjustable Rear Toe Links TR005
BMR Rear Camber Adjustment Lockout Kit WAK761
BMR Billet Aluminium Vertical Links W/Spherical Bushings TCA045

car was already fitted with Magnaride, and has the FP kit (springs, sway bars and software)

Once the new parts were added to the rear, the suspension, now feels like its supper hard, and I’’m basically being jostled down the road. Grip is good, but really uncomfortable.

When the rear subframe was out, without springs, the arms were moving freely, once the new parts are torqued down, primarily the upper and lower arms, the suspension arms were extra stiff.

So I’m trying to find out if anything was missing, not right etc. Or to be expected?
Any advice, experience appreciated.
if anyone has photo’s of an install, that I can use to review my setup, I would be grateful?

Thanks in Advance.

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[Brian@BMVK]

torqued down, primarily the upper and lower arms, the suspension arms were extra stiff

This should not be the case. Recheck your installation. The suspension should articulate freely with everything you changed.

 

[Jsolman]

This should not be the case. Recheck your installation. The suspension should articulate freely with everything you changed.

As far I’m aware, the instructions were followed, know torque was all double checked.

Was wondering, if anything sits between the upper control arm and the chassis mount, with the bolt running through it (poly joint, with metal insert)?
As the chassis mount seemed to just clamp onto it, as the bolt was torqued down.

As this seemed to be the main culprit, that I witnessed, as it was torqued up.
Plan to get it rechecked, though, so wanted to see, if it was normal etc.

 

[Jsolman]

as per this drawing (never took art), where the upper camber arm gets bolted to the rear sub frame, should there be washer between the subframe bracket (black) and upper camber arm(red for the spherical bushing at the inner end)?

 

[Brian@BMVK]

Was wondering, if anything sits between the upper control arm and the chassis mount, with the bolt running through it (poly joint, with metal insert)?
As the chassis mount seemed to just clamp onto it, as the bolt was torqued down.

The insert sits just proud of the poly bushing. Either way it needs to be greased so that it can rotate freely about the insert.

This still seems like something else is wrong. Without shock and spring on the car it should move up and down by hand without too much force.

 

[Radiation Joe]

I installed the BK-055 a couple of weeks ago. My car already has the Ford spherical at the rear of the control arm. I had a local shop do the work, which involved taking out the rear subframe. So consequently, most of my suspension pieces were retorqued during the process.
When I got the car back, the rear suspension felt completely bound up. I went through the rear suspension in my driveway, on ramps and reclocked every bushing. That fixed it. From your list it looks like the only one that might be impacting your ride is the bushing between the LCA and the knuckle. That one really popped when I loosened it. Did you clock the bushings that had been loosened previously?
Now, replacing LCA Bushings with bearings changes the whole feel of the rear suspension. Without a doubt, the rear feels significantly stiffer over small to medium bumps. This is due to loss of compliance from those old bushings. But it rides significantly better over medium to large bumps; and the increase in control is unbelievable. Until two days ago, I hated the rear suspension in my car. Now I'm headed to the front end, since it is no longer the golden child.

 

[JP15.0096.RS3PH2]

The steeda bushings did stiffen it up alot. I also did.. CB005, CB762?, Diff bushings, ford toe replacement joint, BMR toe links, steeda locators.. it is solid

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